Some fair points here foot, right from the database I helped compile. My forgetfulness of these very figures is a bit embarassing. Do look and think a bit deeper though. No one is saying the M3 hands the RS4 a beating. Most reasonable folks know and accept them to be pretty darn close rivals in most areas that matter. However, in thinking this whole loss thing through consider:

Ignore the 0-60 mph, 100km/h, you know better. Those times are traction limited and even the power sapping quattro can do as good or better than an equivalent power to weight ratio car.

The Audi RS4 weighs more than the M3. There seems to be massive diagreement between US specs and European ones for the RS4 weight and no real quorum anywhere. However, it seems to me the car is very close to 4,000 lbs.

The distribution of times and particularly its best times are more indicative of a cars ultimate potential than its average times.

In this list, obviously focused around the M3, there are way more M3 data points. If you had an equally large sample, from an equally wide range of sources, I guarantee you would find the the average values for M3 figures that most heavily depend on power to weight like trap speed and 0-100mph/200kph will be better for the M3.

Each bearing and gear set in a hub or case provides losses, as does the lubrication process, pure, simple, undeniable. The Quattro has way more of these so it will produce higher losses. The wheel dynos and opening post in this thread demonstrate this common sense/well accepted fact perfectly well.

Audi should, eventually, provide a system that mitigates losses better with 100% power transfer to the rear end under normal non traction limited hard acceleration. Then you would only have the weight penalty to deal with.

Sometimes I wonder if the M3 comes with a scientific calculator and a book on physics, so buyers can have all the ammo they want to justify their purchase.

Carbon fiber leather pocket protector optional.

In no way is this a slight against my (obviously very) intelligent friends who have M3's. Just a comment on the thread, which to me is like reading a math book. I can't pay attention. What do all the calculations have to do with driving a car and getting the maximum enjoyment out of it?

I guess I am just a limbic-brain caveman in a C63. Going fast, making lots of noise, and grinning from ear to ear.

To me a balanced view is best. Take into account theory and science and find a way to see real world results as consistent with the science Anyway this is the goal of much of science - to make novel predictions.

Secondly much of the discussion of technology and other such technically oriented threads is as much about automotive engineering as it is about who is the biggest tough guy with the fastest car. Some folks enjoy both aspects.

Lastly when you understand some automotive systems in some level of detail for some folks it truly enhances the actual driving experience. The late Richard Feynman a brilliant Nobel Prize winning physicist told a story about how one fellow could name many birds as they walked around outdoors enjoying nature. Richard couldn't really care less. To him understanding some novel behaviors of the birds and knowing why they did so was much more satisfying. Much of this simply depends on ones background.

Ha! I traded my 2001 A6 4.2 Quattro for the 335xi. From my butt dyno, clearly not all 300 hp cars are equal and not all AWD systems are equal.

I would say that's clearly true. You describe torque splits which I'm sure are different from Audi - but of course that's not the point I'm asking you about. It's also true not all 300 HP cars are equal. As a for instance, I'm sure you're aware of the true 335 power - something around 10% above spec as typically measured on chassis dynos. So let's just ignore that part of your comment, shall we? It's a little subterfuge on your part in order to "prove" how the Audi awd is a power sucker compared to the xi.

Quote:

Originally Posted by T Bone

BTW, a A6 4.2 on paper is very similar to a 335xi. Both have 300 hp and about 300 ft pounds of torque. The A6 weighs 3638 pounds and the 335xi weighs over 3700 pounds.... But the 335xi is in the 13s and traps over 100 mph....this couldn't be clearer data that something is intercepting the power between the flywheels and the wheels.

I'm a little taken aback. You and I know the A6 4.2 is a pig off the line with its tall gearing, while your more aggressively geared xi can launch like a ball bearing out of a slingshot with either boost building against the converter or big revs and sudden clutch. Either way, you're making big power right away while the Audi struggles against those 2.73s. Then there's the aforementioned underrating of the 335, based on average chassis dyno numbers. Finally, our A6 4.2s weighed 4120 pounds with a half tank of fuel (at least mine did, on certified scales), and the current model is listed at 4222, full of gas.

I don't know what you're trying to do here, but once again, do you have anything that actually demonstrates your assertion?

Anything?

I personally don't actually give a damn about "defending" Audi, but Jesus, guy, if you're just spouting off because you don't like Audi, say so, and we'll call it a day and move on.

Some fair points here foot, right from the database I helped compile. My forgetfulness of these very figures is a bit embarassing. Do look and think a bit deeper though. No one is saying the M3 hands the RS4 a beating. Most reasonable folks know and accept them to be pretty darn close rivals in most areas that matter. However, in thinking this whole loss thing through consider:

Ignore the 0-60 mph, 100km/h, you know better. Those times are traction limited and even the power sapping quattro can do as good or better than an equivalent power to weight ratio car.

The Audi RS4 weighs more than the M3. There seems to be massive diagreement between US specs and European ones for the RS4 weight and no real quorum anywhere. However, it seems to me the car is very close to 4,000 lbs.

The distribution of times and particularly its best times are more indicative of a cars ultimate potential than its average times.

In this list, obviously focused around the M3, there are way more M3 data points. If you had an equally large sample, from an equally wide range of sources, I guarantee you would find the the average values for M3 figures that most heavily depend on power to weight like trap speed and 0-100mph/200kph will be better for the M3.

Each bearing and gear set in a hub or case provides losses, as does the lubrication process, pure, simple, undeniable. The Quattro has way more of these so it will produce higher losses. The wheel dynos and opening post in this thread demonstrate this common sense/well accepted fact perfectly well.

Audi should, eventually, provide a system that mitigates losses better with 100% power transfer to the rear end under normal non traction limited hard acceleration. Then you would only have the weight penalty to deal with.

Swamp, near as I can tell, the RS4 performs about the way it should against the M3 in an acceleration contest, taking into account the weight difference, and the undeniable fact that anybody's awd takes more power to run than a comparable rwd system. You're right that more data points would be better, but frankly, just looking at those numbers (and others that I've seen), the differences both feel about right and come out about right when doing very basic analysis.

As we've discussed previously, a system that can apportion power to 100% anywhere is preferable, but when you look around out there at all those available systems, Quattro comes up with decent marks.

I know you're not taking any particular position, but just thought I'd take a break from my discussion with the so far content-free guy.

I would say that's clearly true. You describe torque splits which I'm sure are different from Audi - but of course that's not the point I'm asking you about. It's also true not all 300 HP cars are equal. As a for instance, I'm sure you're aware of the true 335 power - something around 10% above spec as typically measured on chassis dynos. So let's just ignore that part of your comment, shall we? It's a little subterfuge on your part in order to "prove" how the Audi awd is a power sucker compared to the xi.

This is a popular opinion but BMW / SAE has a rating of 300 hp..... sure there can be games but as you well know the ECU can make adjustments.....

Are you attributing all the RS4 kills to gearing?

Quote:

I'm a little taken aback. You and I know the A6 4.2 is a pig off the line with its tall gearing, while your more aggressively geared xi can launch like a ball bearing out of a slingshot with either boost building against the converter or big revs and sudden clutch. Either way, you're making big power right away while the Audi struggles against those 2.73s. Then there's the aforementioned underrating of the 335, based on average chassis dyno numbers. Finally, our A6 4.2s weighed 4120 pounds with a half tank of fuel (at least mine did, on certified scales), and the current model is listed at 4222, full of gas.

I don't know what you're trying to do here, but once again, do you have anything that actually demonstrates your assertion?

Anything?

I personally don't actually give a damn about "defending" Audi, but Jesus, guy, if you're just spouting off because you don't like Audi, say so, and we'll call it a day and move on.

Bruce

Yes, I was off on the A6 4.2 weight, I was quoting a 2.8.

I am not sure what you want as data and proof. RS4s losing? Personal experience my A6 4.2 felt dead after 150 kph? RS4s losing? The RS4 vs. M3 torque curves on the other thread? Where the torque to the wheels for the RS4 (420hp) is significantly lower than the M3 (414hp).

Sure I don't like Audi because of their dogmatic use of Quattro and their inferior implementation of AWD.

__________________

"Aerodynamics are for people who cannot build engines"......Enzo Ferrari

As I thought, you side step the question and evidence I have provided with a statement like I am as dumb as a shoe........smart.

Your dislike for Quattro and Audi has clouded your judgement to the point that pure logic bears no meaning. What I showed in those video comparisons between a street race and the M5Board race is how rigged the thing is, and the very fact that they charge decent money for those video is unacceptable.

As swamp said the data he helped compile show that the RS4 is as quick.

@Swamp,

I have seen lots of data on the RS4 and to be perfectly honest with you the data here is a fair reflection of the average, yes the M3 is marginally quicker but this is to do with it's weight advantage and nothing to do with how much power the transmission is eating up. TB is a FANBOY plain and simple who prefers to put his fingers in his ears and sing to himself when the words Quattro and Audi are mention.

P.S.

I never want to turn this into a quattro vs rwd debate but as always TB starts the thing and I like to put him right even if he doesn't want to listen.

This is a popular opinion but BMW / SAE has a rating of 300 hp..... sure there can be games but as you well know the ECU can make adjustments.....

Are you attributing all the RS4 kills to gearing?

Not at all. The M3 tends to beat the RS4 because it weighs less. More on that in a moment, but can we now agree that your 335 vs A6 4.2 comparison is nonsense? Hey, I'm not complaining that the 335 is underrated, but the fact remains that the drive wheel power output of these engines is in the 275 - 285 HP arena, which means in turn that the 300 HP "at the flywheel" number is nonsense. In addition, boost against preload (or popping the clutch at high rpm) gives the 335 a huge advantage off the line. That, plus the several hundred pound weight disparity, gives your current car a major advantage over your old car - but it ain't because Quattro is some power-robbing "horrible" powertrain.

Quote:

Originally Posted by T Bone

I am not sure what you want as data and proof. RS4s losing? Personal experience my A6 4.2 felt dead after 150 kph? RS4s losing? The RS4 vs. M3 torque curves on the other thread? Where the torque to the wheels for the RS4 (420hp) is significantly lower than the M3 (414hp).

Sure I don't like Audi because of their dogmatic use of Quattro and their inferior implementation of AWD.

Enough said, (almost).

I've never seen a chassis dyno result on a 335 xi, but you can bet the results will be down compared to a rwd 335 - so you can also expect chassis dyno results to be down on the RS4 compared to the M3. After, all, you're transmitting power through three differentials instead of one, plus the attendant u-joints, cv joints, etc. Then you've got to add in the rolling resistance of the two additional tires on the dyno wheels.

Look, guy, because of awd and the weight differential, you'd expect the RS4's quarter mile trap speeds to be down by between three and four percent, with the ET disparity closer due to the awd launch capabilities. Near as we can tell from the lists, that's where the cars fall.

Bottom line, I'm not trying to say anything about which car is better, just that based on what I see in this string plus my own experience, Quattro is far from "horrible", and it certainly isn't particularly power hungry.

Bruce

PS - Since third gear in our A6 4.2 was good for about 110 mph, it certainly felt very strong to me at 150 kph, and in fact it was at 150 kph and above where our car began to pull on both of the 540s I happened to meet.

PPS - HANS! WAKE UP! THIS IS IMPORTANT*STUFF!

BLUCHER!!

BLUCHER!!

*(albeit inconsequential and anal enough to make you think the participants had to be potty trained at gunpoint)

Not at all. The M3 tends to beat the RS4 because it weighs less. More on that in a moment, but can we now agree that your 335 vs A6 4.2 comparison is nonsense?

No. By your calculations, what is the impact of weight as speed increases? Drag / Drivetrain losses become a higher percentage of the "resisting" force. Additionally, if weight was the key issue, why is the RS4 quicker to 60 (assuming good traction on the M3)?

Quote:

Hey, I'm not complaining that the 335 is underrated, but the fact remains that the drive wheel power output of these engines is in the 275 - 285 HP arena, which means in turn that the 300 HP "at the flywheel" number is nonsense. In addition, boost against preload (or popping the clutch at high rpm) gives the 335 a huge advantage off the line. That, plus the several hundred pound weight disparity, gives your current car a major advantage over your old car - but it ain't because Quattro is some power-robbing "horrible" powertrain.

Modern turbo cars can adjust for ambient conditions much more effectively than N/A cars. Dyno runs can be adjusted or even manipulated as you know. If you know better than BMW / SAE than please share with us.

Quote:

I've never seen a chassis dyno result on a 335 xi, but you can bet the results will be down compared to a rwd 335 - so you can also expect chassis dyno results to be down on the RS4 compared to the M3. After, all, you're transmitting power through three differentials instead of one, plus the attendant u-joints, cv joints, etc. Then you've got to add in the rolling resistance of the two additional tires on the dyno wheels.

Look, guy, because of awd and the weight differential, you'd expect the RS4's quarter mile trap speeds to be down by between three and four percent, with the ET disparity closer due to the awd launch capabilities. Near as we can tell from the lists, that's where the cars fall.

Bottom line, I'm not trying to say anything about which car is better, just that based on what I see in this string plus my own experience, Quattro is far from "horrible", and it certainly isn't particularly power hungry.

Bruce

PS - Since third gear in our A6 4.2 was good for about 110 mph, it certainly felt very strong to me at 150 kph, and in fact it was at 150 kph and above where our car began to pull on both of the 540s I happened to meet.

Sure I would expect the XI to be down on from the regular I. But what is not being addressed is the observed performance gaps of the RS4 and other old school Quattro systems.

It is not weight as the significance of the other forces are much higher after say 70 mph.

Also personally, I remember the A6 4.2 as being slow off the line, a happy 60 - 140 kph type of car and after a few high speed runs, the car was slow.

__________________

"Aerodynamics are for people who cannot build engines"......Enzo Ferrari

This latest video is famous the world over. I hope it is one of the true M5Board videos because I am about to take delivery of an M3 M-DCT (the quick one -(jk)) and the thought on knowing for certain that I will win everytime against an RS4 would be a nice thought.

The reality is that in the real world, on the street, I doubt this will be a true reflection and things will be much, much closer. I am not saying the M3 wouldn't likely win but it wouldn't be a whipping like we see here.

P.S.
Funny that, because that has always been my point on this subject.

Bottom line, I'm not trying to say anything about which car is better, just that based on what I see in this string plus my own experience, Quattro is far from "horrible", and it certainly isn't particularly power hungry.

I'm won't comment on the relative losses comparing Quattro vs. BMW except that the 100% rear bias available on the BMW does help substantially. I think the point is that regardless of the design or manufacturer AWD systems produce a significant amount of loss. If you believe the particular dyno numbers in the OP the RS4 losses are 18% vs. 12% for the M3. This difference is consistent with numbers used in simulation (numbers thanks to you, with my tweaks) of 3% for axles and 1% for a diff (12+2x3+1 = 19). No matter how you slice it 6% is a lot and for cars in this power range it is ~ 25 hp. In lb, at 9 lb/hp, this is ~ 225 lb.

No. By your calculations, what is the impact of weight as speed increases? Drag / Drivetrain losses become a higher percentage of the "resisting" force. Additionally, if weight was the key issue, why is the RS4 quicker to 60 (assuming good traction on the M3)?

Uh, because up until model year 2008 at least, you could wind it up to one rpm short of the limiter and sidestep the clutch? Duh. See below for further commentary.

Quote:

Originally Posted by T Bone

Modern turbo cars can adjust for ambient conditions much more effectively than N/A cars. Dyno runs can be adjusted or even manipulated as you know. If you know better than BMW / SAE than please share with us.

You're kidding, right? There are probably a couple of dozen strings out there on the net in English (and presumably many more than that in other languages) showing that anybody who straps a 335 to a chassis dyno and gets less than about 275 HP on a stick 335 (and about 265 HP in an automatic) immediately goes running to the dealer, demanding to know what's wrong. The other clue is the trap speed. The cars are going a minimum of 104 mph in the quarter mile, with most seeming to cluster in the 105 - 106 range, at least when density altitudes are at 1000 feet or below. We're talking 330 -340 HP here, assuming 3700 pounds with driver.

Where have you been?

Quote:

Originally Posted by T Bone

Sure I would expect the XI to be down on from the regular I. But what is not being addressed is the observed performance gaps of the RS4 and other old school Quattro systems.

I'm not opening this up to all Audis built since the stone age, but what part of this (in my last post) didn't you get?

"Look, guy, because of awd and the weight differential, you'd expect the RS4's quarter mile trap speeds to be down by between three and four percent, with the ET disparity closer due to the awd launch capabilities. Near as we can tell from the lists, that's where the cars fall."

Calling it to within about 1% is pretty specific, doncha think?

Quote:

Originally Posted by T Bone

It is not weight as the significance of the other forces are much higher after say 70 mph.

Other than commenting that weight stays with you from zero to flat out, and aerodynamics loss squares with speed, I have nothing to add on acceleration from, say, 120 to 150 mph. Nothing at all. (It's due to lack of actual knowledge and experience on my part.)

That's not what we're primarily addressing here, though. It's the classic quarter mile, easily addressable through a number of tools and rules of thumb. In that venue, the Audi typically loses to the M3 by just about what you'd expect. Sometimes less, not often more.

Quote:

Originally Posted by T Bone

Also personally, I remember the A6 4.2 as being slow off the line, a happy 60 - 140 kph type of car and after a few high speed runs, the car was slow.

I'm won't comment on the relative losses comparing Quattro vs. BMW except that the 100% rear bias available on the BMW does help substantially.

From previous information (and T Bones' recent post), it seems to me that the bimmer awd is a more sophisticated unit than the classic Audi. Not sure about how substantial the actual performance difference would be, however, since Audi has said for over 20 years that a driven tire exhibits less rolling resistance than one which is just along for the ride. The "not sure" piece is simple ignorance on my part, as I expect that all the info almost anyone would need resides somewhere in the SAE archives. I just don't feel like doing the research to run them down, and then paying for the pertinent articles.

Quote:

Originally Posted by swamp2

I think the point is that regardless of the design or manufacturer AWD systems produce a significant amount of loss. If you believe the particular dyno numbers in the OP the RS4 losses are 18% vs. 12% for the M3. This difference is consistent with numbers used in simulation (numbers thanks to you, with my tweaks) of 3% for axles and 1% for a diff (12+2x3+1 = 19). No matter how you slice it 6% is a lot and for cars in this power range it is ~ 25 hp. In lb, at 9 lb/hp, this is ~ 225 lb.

Agreed. This plus the weight differential is what makes the M3 out-accelerate the Audi over any meaningful distance - meaning the M3 inexorably reels in the Audi after the banzai launch the RS4 is capable of, and keeps going.

You're kidding, right? There are probably a couple of dozen strings out there on the net in English (and presumably many more than that in other languages) showing that anybody who straps a 335 to a chassis dyno and gets less than about 275 HP on a stick 335 (and about 265 HP in an automatic) immediately goes running to the dealer, demanding to know what's wrong. The other clue is the trap speed. The cars are going a minimum of 104 mph in the quarter mile, with most seeming to cluster in the 105 - 106 range, at least when density altitudes are at 1000 feet or below. We're talking 330 -340 HP here, assuming 3700 pounds with driver.

I am trying to turn over a new leaf. Since we are now on 335s and have dispensed with the Audi conversation.....

There is a popular rumor on the internet that 335s and GTRs are underrated. There is also a wide variance between the E/T and Trapsepeed methods. We have no way to prove anything unless we had an engine dyno.

Another observation that you can stew about....a stock E46 M3 is faster than a stock 335i at sea level.

Enjoy 333 vs. 300 hp

__________________

"Aerodynamics are for people who cannot build engines"......Enzo Ferrari

I am trying to turn over a new leaf. Since we are now on 335s and have dispensed with the Audi conversation.....

There is a popular rumor on the internet that 335s and GTRs are underrated. There is also a wide variance between the E/T and Trapsepeed methods. We have no way to prove anything unless we had an engine dyno.

Another observation that you can stew about....a stock E46 M3 is faster than a stock 335i at sea level.

Enjoy 333 vs. 300 hp

Can someone explain how one person using video evidence is proof and another is called as dumb as a shoe for doing the same.

Don't figure.

Not the huge pulling away we see in the M5Board videos and this M5 is kicking out 525hp. If it can't walk the RS4 in such a fashion as we see in thise videos than what chance has an M3 got with over a 100hp less.

Surely this Porsche should have reeled it in based on the evidence in M5Board videos.

...Since we are now on 335s and have dispensed with the Audi conversation.....

I assume that's because you now agree that the RS4 performs just about the way it ought to against the M3?

Quote:

Originally Posted by T Bone

There is a popular rumor on the internet that 335s and GTRs are underrated. There is also a wide variance between the E/T and Trapsepeed methods. We have no way to prove anything unless we had an engine dyno.

There is a plethora of evidence indicating how powerful the 335 is compared to its rating, including dozens of dyno runs and the undeniable trap speed evidence from road tests and individual runs. ET? Don't know why you brought it up, because I didn't, and I don't regard it as a reliable indicator of power.

GT-R? The jury is still out on that one as far as I'm concerned. We're seen trap speeds from 111 mph to about 120 mph on U.S.- spec models, so we'll see more as more road test data becomes available.

Quote:

Originally Posted by T Bone

Another observation that you can stew about....a stock E46 M3 is faster than a stock 335i at sea level...

Yes, marginally. The E46 has a minor advantage, based on road test evidence. That's because the M3 and 335 make similar power, but the M3 weighs around 150 pounds less.

I assume that's because you now agree that the RS4 performs just about the way it ought to against the M3?

No, it doesn't at high speeds. Repeating it won't make it so.

Quote:

There is a plethora of evidence indicating how powerful the 335 is compared to its rating, including dozens of dyno runs and the undeniable trap speed evidence from road tests and individual runs. ET? Don't know why you brought it up, because I didn't, and I don't regard it as a reliable indicator of power.

Yes I have seen the "evidence". We all know dyno runs not reliable and in fact can be manipulated and we only see the best runs.

This is why I proffered the video of a 333 hp E46 M3 vs a stock 300 hp 335i, many variables are removed and it is real world. A 300 hp car is behaving as it should.

Against the 300 hp A6, the 300 hp is significantly faster across the board and if it is not the motor, what else is there?

Quote:

GT-R? The jury is still out on that one as far as I'm concerned. We're seen trap speeds from 111 mph to about 120 mph on U.S.- spec models, so we'll see more as more road test data becomes available.

Hey did you call out the testing methodology error in one of the rags where they posted a 124 mph trap speed??

111 mph to 115 mph is about right for a 480 hp car.

__________________

"Aerodynamics are for people who cannot build engines"......Enzo Ferrari